The present invention relates to a cosmetic skin treatment method using a patch configured to be applied to the skin in a cleansing mode to cleanse the skin and in a treatment mode to provide one or more treatments to the skin. The invention also relates to a cleansing and treatment patch that can be used to practice the method.
Conventional methods employ patches that allow active compounds to be administered transdermally for the purpose of carrying out a systemic treatment. Such conventional patches generally have a structure that includes several successive layers. The first layer is a support layer. The support layer is generally occlusive. The second layer is a composition that is fastened to the support layer and often contains one or more active compounds. The composition layer is the layer that contacts the skin during treatment. The composition layer may also include an adhesive to facilitate fastening of the patch to the skin. The last layer is a detachable cover. The cover generally sealably covers the composition layer to protect it from external contamination during storage of the patch prior to use.
Occlusive beauty care patches are also known in the art. Those patches are configured to allow active compounds to penetrate the epidermis. They generally do not include an adhesive since they often include aqueous or hydrophilic formulations. Occlusive beauty patches are intended for skin treatment and are generally placed on the skin for an application time that may range from 15 minutes to 8 hours.
Some occlusive beauty care patches are applied overnight for administering an active agent to the epidermis. Those patches often exhibit a very high level of adhesion to the skin and therefore can damage the skin when they are removed. In particular, patches with strong adhesives can cause cracking, painful red blotches, and/or inflamation to skin that has already become sensitive due to prior treatments.
Dry masks are also known. Dry masks require the user to moisten the mask prior to applying the mask. Dry masks are generally intended for deep cleansing of the skin, especially of the pores. However, dry masks tend to dry out the skin.
Dehydrated patches that can be remoistened with water are also known. Those patches include water-soluble polymers. Dehydrated patches are removed after drying to desquamate and cleanse the skin.
Additionally, self-adhesive patches that comprise a hydrophobic matrix made of polyurethane, polyacrylate, polyvinyl, or silicone are known. Those patches include water-absorbing particles. The water absorbing particles re-dissolve water-soluble active agents contained in the matrix, forming a suspension. Patches of this kind, however, exhibit a relatively limited level of adhesion.
Dry non-bonding treatment-cloth products that are moistened and do not dry out are also known. They are generally used to carry out facial beauty care treatments.
In light of the foregoing, there is a need in the art for an improved cosmetic skin treatment method and an improved cleansing and/or treatment patch.
Accordingly, the present invention is directed to a cosmetic skin treatment method and a cleansing and/or treatment patch that obviate one or more of the short-comings of the related art.
A preferred object of the invention is to provide a treatment method that allows a user to apply a single patch to cleanse the skin and to allow treatment of the skin.
Another preferred object of the invention is to provide a dual purpose patch that can be used in a cleansing mode and a treatment mode. Having a dual purpose patch obviates the risk of confusing different types of patches.
Preferably, in addition to cleansing the skin, the patch of the present invention can be used to provide a treatment. In particular, the patch can provide a treatment in which one or more cosmetically active compounds are released onto the epidermis.
Using the patch in the cleansing mode preferably prepares the skin for treatment by removing impurities present on the surface of the skin. For example, such impurities include residues due to environmental pollution, dead skin cells, sebum plugs, blackheads, and perspiration residues.
After the patch is used to cleanse the skin, another patch of the same type, or even the same patch, can be applied to the surface of the skin to provide a treatment. For example, the treatment may include an emolliating, moisturizing, softening, cicatrizing, regenerating, anti-wrinkling or tautening, sun-screening, soothing, self-tanning, or lightening action on the skin. The treatment may also include opening or closing pores of the skin.
A further preferred object is to provide a simple, alternating and/or cumulative skin cleansing and skin treatment using the same type of patch.
Still another object of the invention is to provide two different treatments depending on whether the patch is applied to dry skin when the patch is in a dried state or to skin when the patch is in a wet state (i.e., at least one of the patch and the skin is moistened).
Another object of the invention is to provide a patch incorporating various cosmetically active compounds which, apart from removing impurities from the skin, provide a treatment to the skin, such as a moisturizing, softening, emolliating, cicatrizing, regenerating, soothing, self-tanning, lightening, anti-wrinkling, sun-screening action, or grease-reducing treatment.
An additional object of the invention is to prepare the skin for a skin treatment by cleansing the skin, thereby increasing the effectiveness of the skin treatment.
It should be understood that the invention could still be practiced without performing one or more of the preferred objects and/or advantages set forth above. Still other objects will become apparent after reading the following description of the invention.
To achieve these and other advantages, and in accordance with the purposes of the invention, as embodied and broadly described herein, the invention includes a cosmetic skin treatment method. The method includes providing a patch configured to be used in both a cleansing mode and a treatment mode. The patch includes a polymeric matrix and a reinforcing member. The polymeric matrix includes at least one to cosmetically active compound and at least one water-absorbent compound. The patch is configured to adhere to dry skin and also to adhere to skin when at least one of the patch and skin is moistened. Preferably, an adhesion force between the patch and dry skin is greater than an adhesion force between the patch and skin when at least one of the patch and skin is moistened. The method also includes selecting at least one of the cleansing mode and the treatment mode. When the cleansing mode is selected, the method further includes applying the patch to an area of dry skin so that the polymeric matrix adheres to the skin for a time sufficient to allow at least one impurity in the area of skin to become attached to the polymeric matrix. Thereafter, the patch is removed from the area of the skin while said at least one impurity is attached to the polymeric matrix. When the treatment mode is selected, the method further includes moistening at least one of the patch and an area of the skin. Then, the patch is applied to the area of skin so that the patch adheres to the area of skin. After applying the patch, the cosmetically active compound is allowed to contact the area of skin. The cosmetically active compound is preferably allowed to dissolve in the moisture. Preferably, the patch is removed from the area of skin.
Although in the treatment mode either the patch or the skin can be moistened, moistening of the skin is the preferred method.
The patch preferably includes a self-adhesive matrix allowing the patch to adhere to dry skin. Preferably, at least a substantial portion of the area of the patch contacts the skin. When the patch is removed, impurities on the surface of the skin are preferably removed due to the mechanical action of the adhesive. Preferably, the polymeric matrix includes active agents that facilitate removal of the impurities. For example, active agents may be transferred to the skin when the patch is removed from the skin.
The at least one water absorbent compound is preferably separated from the free surface of the patch by a very thin layer of adhesive material. When moisture is applied to the patch by moistening the patch or by contacting the patch with moistened skin, the at least one water absorbent compound preferably absorbs moisture and forms a gel or a network of water-swollen fibers, into which the at least active compound is dissolved. When the at least one active compound is dissolved in the gel of water-swollen fibers, it can be brought into contact with the skin. Because the at least one water absorbent compound absorbs some of the moisture, a certain number of anchoring points preferably remain between the matrix and the skin, thereby allowing sufficient adhesion of the patch to the skin. When moisture is applied to the patch, the adhesion force between the patch and the skin is preferably substantially less than the adhesion force between the patch and dry skin.
In a preferred embodiment, the method includes selecting both the cleansing mode and the treatment mode, wherein the cleansing mode is performed prior to the treatment mode. Although the treatment may be performed immediately after the cleansing, the cleansed skin is preferably allowed to rest after the cleansing, for example, the cleansed skin is allowed to rest for a period ranging from about 30 minutes to about 12 hours.
In another embodiment, the method includes selecting both the cleansing mode and the treatment mode, wherein the treatment mode is performed prior to the cleansing mode. For example, an emolliating treatment is applied prior to cleansing to open the pores to facilitate a subsequent deep cleansing.
Preferably, the application of the patch in cleansing mode is carried out alternately with the application in treatment mode. However, it may be advantageous, especially when the skin is greasy, to carry out a number of applications in cleansing mode alternating with a number of applications in treatment mode.
Preferably, when using the patch in the cleansing mode, the patch is applied for a period ranging from about 5 seconds to about 5 minutes.
When the patch is used in the treatment mode, the application may be carried out for a period ranging from about 5 minutes to about 30 minutes, or even about 60 minutes, if required.
In another aspect, the invention includes a cleansing and treatment patch. The patch includes a reinforcing member and a polymeric matrix. The polymeric matrix includes at least one cosmetically active compound and at least one water-absorbent compound. The patch is configured to adhere to dry skin and also to adhere to skin when at least one of the patch and skin are moistened. Preferably, an adhesion force between the patch and dry skin is greater than an adhesion force between the patch and skin when at least one of the patch and skin are moistened. The patch is configured so that when the patch is used in a cleansing mode and the patch is applied to an area of dry skin, the patch adheres to the area for a sufficient time to allow at least one impurity in the area of skin to become attached to the polymeric matrix so that the impurity is removed from the area of skin when the patch is removed. The patch is also configured so that when the patch is used in a treatment mode and at least one of the patch and an area of skin is moistened, at least some of the cosmetically active compound contacts the area of skin. When the patch is used in treatment mode, preferably at least some of the cosmetically active compound is dissolved in the moisture.
The cosmetically active compounds that can be incorporated into the matrix of the patch are preferably chosen from emollients, moisturizers, softening agents, keratolytic agents, desquamating agents, cicatrizing agents, regenerating agents, anti-wrinkle agents, tautening agents, sun-screen agents, soothing agents, self-tanning agents, bleaching agents, lightening agents or mixtures thereof. In addition, antioxidants, free-radical scavengers, liporegulating agents, anti-acne agents, anti-ageing agents, anti-inflammatory agents, refreshing agents, vascular protective agents, antibacterials, antifungals and nourishing agents may be incorporated into the polymeric matrix.
In a preferred embodiment, the at least one cosmetically active compound is dispersed homogeneously in the polymeric matrix in particulate form. Homogeneous dispersion of the at least one cosmetically active compound can be beneficial, especially when the patch is applied in treatment mode to wet skin, since the at least one cosmetically active compound dissolves substantially in the matrix, resulting in even penetration.
The at least one cosmetically active compound is used especially in the cleansing mode. It is preferably a compound whose action allows the impurities in the skin to become detached from the skin (for example, keratolytic agents that detach dead skin cells). There may also be one or more compounds contained in the matrix that are capable of directly absorbing the fatty or aqueous secretions of the skin, such as sebum or perspiration. For this purpose, it is possible to use materials such as kaolin powder, burnt Sienna, zeolites, polyamide particles (especially those sold under the name ORGASOL(copyright) by the company Atochem). These particles also may have a softening effect on the skin. Powder of expanded thermoplastic microspheres, sold under the brand name EXPANCEL(copyright) by the company Kemanord Plast, and modified starch powders sold by the company National Starch under the brand name Dry Flo(copyright) may also be used to absorb fatty or aqueous secretions. It is further possible to use a mixture of such materials.
The active compounds having a cleansing effect that may be incorporated into the matrix include, in particular, keratolytic agents such as alpha- and beta-hydroxycarboxylic acids and beta-ketocarboxylic acids, their salts, amides and esters, and preferably alpha-hydroxy acids such as glycolic acid, lactic acid, tartaric acid, malic acid, citric acid, mandelic acid and, in general, fruit acids and beta-hydroxy acids such as salicylic acid and its derivatives, especially alkylated derivatives such as 5-(n-octanoyl)salicylic acid and its esters. Antibacterials such as clindamicyn or erythromycin phosphate, or antibiotics of the tetracyclin type may also be used. Such active compounds are preferred when the skin has a tendency towards acne and can be used in particular in combination with emollients, softening agents, especially honey and waxes and/or cicatrizing agents, especially certain mineral salts, such as zinc oxide. They may also be combined with astringent agents such as tannins and/or aluminium and/or zirconium chlorohydrates.
The at least one active compound may include one or more active agents chosen from ascorbic acid and its biologically compatible salts and esters, enzymes, tautening agents, such as protein, soya and wheat powders, hydroxylated polyacids, sucroses and their derivatives, urea, amino acids, oligopeptides, water-soluble plant and yeast extracts, protein hydrolysates such as collagen and elastin hydrolysates, hyaluronic acid, mucopolysaccharides, vitamins B2, B6, H and PP, panthenol, folic acid, acetylsalicylic acid, allantoin, kojic acid, and hydroquinone.
The matrix may also include at least one liposoluble compound chosen from the following compounds: D-xcex1-tocopherol, DL-xcex1-tocopherol, D-xcex1-tocopherol acetate, DL-xcex1-tocopherol acetate, ascorbyl palmitate, vitamin F and vitamin F glycerides, vitamins D, vitamin D2, vitamin D3, retinol, retinol esters, retinol palmitate, retinol propionate, xcex2-carotene, D-panthenol, farnesol, farnesyl acetate; jojoba and blackcurrant oils rich in essential fatty acids; asiatic acid, madecassic acid, asiaticoside, total extract of centella asiatica, xcex2-glycyrrhetinic acid, xcex1-bisabolol, ceramides such as 2-oleoylamino-1,3-octadecane; phytanetriol, milk sphingomyelin, phospholipids of marine origin, rich in polyunsaturated essential fatty acids, ethoxyquin; extract of rosemary, extract of melissa, quercetin, extract of dried microalgae, and steroidal anti-inflammatory drugs.
By way of example, the emollient can be chosen from: volatile and non-volatile silicones, polydiorganosiloxane-polyoxyalkylene copolymers; natural and synthetic oils such as mineral, plant and animal oils; fats and waxes; fatty alcohols and acids, and their esters; esters and ethers of (poly)alkylene glycols; hydrocarbons such as isohexadecane, petrolatum and squalane; lanolin alcohol and its derivatives; animal and plant triglycerides; and stearyl alcohol.
The moisturizer is preferably chosen from: glycerol, sorbitol and its derivatives, propylene glycol, dipropylene glycol, butylene glycol, D- or DL-panthenol and their derivatives.
Preferably, allantoin is chosen as a softening agent.
The desquamating agent is chosen from: alkylated derivatives of salicylic acid, 5-(n-octanoyl)salicylic acid, alpha- and beta-hydroxycarboxylic acids and beta-ketocarboxylic acids, their salts, amides and esters.
The tautening agents are preferably chosen from alpha- and beta-hydroxycarboxylic acids and beta-ketocarboxylic acids, their salts, amides and esters; alicylic acid, ascorbic acid, azelaic acid, retinol and their derivatives.
When sunscreen agents are present, they are preferably chosen from the UV-A filters and/or the UV-B filters normally used in sunscreen compositions.
As a soothing agent, xcex1-bisabolol can be chosen.
When a self-tanning agent is used, it is chosen from dihydroxyacetone and derivatives of hydroxynaphthoquinone.
Preferably, the lightening or bleaching agent is chosen from citric acid, hydroquinone, kojic acid and ascorbic acid.
Preferably, the polymeric matrix includes a silicone adhesive. More preferably, the polymeric matrix includes a polyacrylic or polyvinyl adhesive, such as a self adhesive acrylic polymer sold by the company MAPEI, S.p.A. under the brand name AGXL(copyright).
The adhesion force of the patch to dry skin (when used in cleansing mode) preferably ranges from about 300 g/cm2 to about 800 g/cm2 (i.e., a force exerted perpendicular to the plane of the adhesive surface needed to pull the patch off of the skin). The adhesion force of the patch when moistened preferably ranges from about 20 g/cm2 to about 300 g/cm2.
The surface of the matrix that contacts skin may be smooth or may have asperities or raised features. The thickness of the matrix may vary, depending on the amount of the at least one active compound and the at least one water-absorbent compound used. Preferably, the thickness ranges from about 5 microns to about 500 microns.
In an aspect of the invention, when the matrix initially includes one or more solvents, after the solvents have evaporated, at least some of the particles of the at least one active compound and/or at least some of the particles of the water-absorbent compounds and/or agglomerates formed from such particles, emerge from an application surface of the adhesive matrix. In practice, these particles generally do not emerge directly, but remain coated with a very thin layer of the matrix. By way of example, the particles have a thickness that ranges from a few microns to a few hundred microns. Preferably, the thickness of the particles ranges from about 10 microns to about 100 microns, and even more preferably from 10 microns to about 70 microns. Preferably, the average thickness of the matrix (after evaporation of the solvents) is less than the largest dimension of fillers and/or particles of the at least one active compound and/or particles of the at least one water-absorbent compound present in the matrix. Where appropriate, if the fillers or particles form agglomerates, (i.e., groups) the average thickness of the matrix is preferably less than the largest dimension of said agglomerates. This arrangement allows the formation of an interface layer when moisture is applied to the patch for the treatment mode. The interface layer is preferably formed by at least one water absorbent compound swollen with moisture (i.e., water), especially in the form of a gel. Preferably, the active compounds are capable of dissolving in the interface layer. The interface layer is preferably between the matrix and the skin, thereby allowing the at least one active compound to be brought into contact with the skin. The thickness of the interface layer preferably ranges from about 50 microns to about 100 microns. Although only a small portion of the adhesive matrix is in contact with the skin, resulting in a reduced adhesion to the skin, the adhesive matrix generates sufficient adhesion force to maintain the patch on the skin due at least in part to the intrinsic adhesion of the gel.
Preferably, the at least one water-absorbent compound comprises particles dispersed in the matrix. When the particles of the at least one water-absorbent compound contact moisture present on the skin (e.g., after moistening the skin), the particles of the water-absorbent compound absorb moisture, thereby facilitating dissolving of a water-soluble solid active compound when a water soluble solid active compound is present in the matrix. This in situ solubilization of the water-soluble active compound provides for almost instantaneous bioavailability. Additionally, interaction with other compounds present in the polymeric matrix is minimized. The moisture present on the skin (or on the patch before application) acts as a solublizer for a water-soluble active compound.
Representative water-absorbent compounds that may be present in the polymeric matrix in the dispersed state include superabsorbent crosslinked polyacrylates having a high degree of swelling in water, such as those sold by the company Norsolor under the brand name AQUAKEEP(copyright); polyvinyl alcohol; carboxyvinyl polymers such as those sold by Goodrich under the brand names CARBOPOL(copyright); semi-synthetic derivatives of cellulose such as carboxymethylcellulose; starches, biogums such as xanthan gum, guar gum, gum arabic and gum tragacanth, biosaccharides, scleroglucans; casein; phytocolloids, such as alginates, carragenates and agar agar; gelatin and cotton fibers.
It is particularly preferable to use superabsorbent crosslinked polyacrylates, whose presence in the dispersed state in a hydrophobic polymeric matrix allows a high water content to be built up and favors, after hydration, better availability of the particles of other active compounds possibly present in the matrix.
The at least one water-absorbent compound defined above is preferably present in an amount ranging from about 0.2% to about 20% with respect to the total weight of the matrix, and even more preferably ranging from about 0.5% to about 10% with respect to the total weight of the matrix.
Essential oils may be included in the polymeric matrix. By way of example, mention may be made of lavender, mint, pepper, nutmeg, clove, cedar, wheatgerm, calophyllum, cartham, coriander and fruit pip (grape, blackcurrant, orange and kiwi) oils. Mint oil contains a high level of menthol which, when included in the matrix in microcrystalline form, can provide skin with a feeling of freshness.
The reinforcing member preferably includes any suitable material impermeable to the active compounds contained in the polymeric matrix. The reinforcing member not only has the function of reinforcing the polymeric matrix, but also serves as a coating for protecting the matrix. The reinforcing member may have the same size as the polymer matrix or it may be larger so that it extends beyond the periphery of the polymeric matrix.
In an embodiment, the reinforcing member is occlusive. By way of example, the reinforcing member includes a thermoplastic chosen from high-density and low-density polyethylenes, polypropylenes, polyvinyl chlorides, ethylene-vinyl acetate copolymers, polyesters and polyurethanes, and polyethylene terephthalate. These materials may also be present in the form of a laminate with at least one metal foil such as aluminium foil.
The reinforcing member preferably has a thickness suitable for providing support and protection functions. Preferably, the thickness of the reinforcing member ranges from about 20 xcexcm to about 1.5 mm. Preferably, the reinforcing member is flexible enough to be able to match the profile of the skin and not to cause the user any feeling of discomfort.
In an alternate embodiment, the reinforcing member is non-occlusive. For example, the reinforcing member is chosen from paper, meshes of porous thermoplastic, meshes of perforated thermoplastic, woven fabrics, and nonwoven fabrics, such as perforated nonwoven fabrics. Preferably, when the reinforcing member is a mesh, the reinforcing member is embedded in the polymeric matrix.